Power set-works for sawmills.



DB WITT G. PRESCOTT. POWER SET WORKS FOB SAWMILLS.

APPLICATION FILED PT. 24, 1904. 904,806.

Patented Nov. 24, 1908.

8 SHEBTB-SEEET 1.

DE WITT C. PRESGOTT.

POWER SET WORKS r03 SAWMILLS;

APPLIOATION FILED SEPT. 24, 1904. Patented Nov 24,

3 SHEETS-SHEET 2 DE WITT G. PRESCOTT. POWER SET WORKS Ion SAWMILLS.

3 SHEETS-SHBET 3.

Patented Nov. 24, 1908.

APPLICATION FILED SEPT. 24, 1904. 904,806.

424/. 4 20442? P/Wa .1 )VL @4141 v DE WITT U. PRESCOTT,

PATENT OFFICE.

OF CHICAGO, ILLINOIS.

POWER SET-WORKS FOR SAWMILLS.

Specification of Letters Patent.

Patented Nov. 24, 1908.

Application filed September 24, 1904. Serial No. 225,822.

To all whom it may concern:

Be it known that I, DE VVITT C. Pnnsoorr, a citizen of the United States, and resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Im rovcments in Power Set-Works for Sawmills, of which the following is a specification, and which are illustrated in the ac The invention relates to mechanism for advancing the knees of a saw-mill carriage, and particularly to the adjustable ositive stop employed for limiting the stro e of a motor for driving mechanism of this char- 'acter.

The. invention consists in the device hereinafter described and claimed, and which is illustrated in the accompanying drawings, in whicht Figure 1 is a side elevation of the machine including a motor, some of the parts being broken away; Fi 2 is a detail end elevation of the machine; igs. 3, 4 and 5 are detailsections on the line 33, 44, and 5-5, respectively, of Fig. 2; Fig. 6 is a detail of one of the parts; and Fig. 7 1s a detail section on the line 77 of Fig. 3.

Any form of motor may be employed, and the invention is not restricted to any particular form of mechanism for transmitting power from the motor to the set shaft.

There is shown in the drawings a reci rocating steam engine mounted upon a be or frame 10, adapted to be attached to a saw mill carriage, the cylinder of the engine being represented at 11, its steam chest at 12, the hand lever for controlling the throttle valve at 13, the shaft to which such lever is attachedat 14, a crank mounted upon this shaft at 15, and the valve-stem of the motor connected with this crankat 16. The details of the engineare not shown, but the valvegear is represen ed as of the ty e formin the subject of my Patent No. 45,520, 0

December l, 1903.

A cross-head 17 is attached to the piston rod 18 of the motor and rcciprocates u on the guide-rods 19, which are supported at one end by the cylinder and at the other ?on an upstanding bracket of the bed 10.

he cross-head 17 is provided with a gear. rack 20, engaging a segmental pinion 21, mounted upon a rocker shaft 22. which canries a pair of oppositely-directed crank-arms 23, 24, connecte companying drawings, forming a part theref ing the stroke of the motor.

by means of links 26, 26,

f with pair of pawl carriers 27, 28, mounted to oscillate upon the set shaft 29 and carrying pawls engaging the ratchet wheel 30 upon the same shaft. This transmission mechanism is also of common construction and isnot of the essence of the inyention. The cross-head 17 carries a head 31, located between the guide rods 19 and adapted for contact with the positive stop for determin- The stop with which the head 31 cooperates is shown at 32, and is located between the guide-rods 19 and keyed upon a shaft 33, journaled within suitable boxes carried by the bracket of the bed-frame 10 upon which the outer ends of the guide-rods are mounted, the shaft being located approximately on the plane ofthe head 31. The stop 32 is in spiral or substantially convolute form, so that as the shaft 33 is turned a radius of the stop in line with the head 31 constantly varies in length, accordingly varying the stroke of the englne, which is limited by the engagement of the head with the sto The stop is controlled by a hand whee 34, fixed 'upon the shaft 33, and preferably provided with a plurality of knobs or hand-pieces 35, which may be easily rasped by the operator. The face of this w eel is provided with a scale, as shown at 36, cotiperating with an indicator 37'mounted upon a bracket-arm 38 ris-. ing from the frame 10. A pawl 39, pivoted upon the bracket-arm 38, cooperates with ratchet teeth 44, also formed upon the rim of thewheeI 34, for frictionally holding the wheel in an adjusted position. The pawl is shown ashaving a tail-piece 40 projecting downwardly, act the rear face of the bracket arm 38, whic issocketed to receive an expansion spring 41, which reacts against this tail-piece sons to hold the nose of the pawl into engagement with the ratchet teeth. The pawl is controlled by a cam 42 actuated" by a lever-arm '43. Preferably the hand wheel 34 is alsoprovided with an annular templet plate 45, secured to its inner face and ro ecting radially .be ond the ratchet teetli This plate is pre erably of steel and quite thin, so that it may be easily cutwith a file and will be notched, as shown at 46, as may be required by the exi encies of the particular situation in which t e machine is to be used.

Usually a saw mill is operated for a considerable period of time in the manufacture of certain sizes of lumber, and the work in notched to correspond with the several sizes of material being manufactured, and as these usually number but three or fourthe operator can at a glance bring the wheel to any desired position.

he pawl 39 is provided with a single tooth 47, adapted to enter the notches 46, and while this tooth is riding on the smooth portion of the templet plate the awl is held out of en agement with the rate et teeth 44. Preferabfi the latter teeth are V-shaped and merely su plement the tooth 46. When the templet p ate is notattached to the wheel, however, it is controlled only by these teeth and their V-form permits the operator to turn the wheel without lifting the pawl.

As shown at 46 the templet plate is provided with series of three notches close to gather, as providing for setting the machine or the cuttin of material to the exact size, or sli htly be ow or above that size,it being t e practice to thus vary the thickness according to the kind of lumber being mannfactured. For the convenience of the operator a stop 48 may be provided for limitmore short strokes to brin ing the movement of the wheel 34 the latter carrying a pin 49 into the path of which the stop 48, shown asa bracket secured to a per:

tion of the bed-frame 10, projects.

In the firstadjustment of a cant upon the headZ-la'locks of a saw-mill carriage, the operator'may desire to give the motor one or the cant to. the exact position desired, an especially with inexperienced 0 erators it is advisable to rovide a sto or the motor which will so '1; its stro e that the pawls cooperatingthrough the face of the stop 32 at its largest radius and providing the bolt with a locknut 51, by means of which it may be fired in an ad usted position. This bolt may be so set that when it isin the path of the head 31 the stroke of the-motor will be restricted as may be desired.

I claim as my invention 1. In a. saw mill'set-works, in combination, a reciprocating part, and a stop located in the path of such part and comprising a pivotal member, the periphery of which constitutes its abuttin face and is substantially in the form 0% a, convolute curve, whereby the finest adjustments may be attained by the pivotal movement of such part.

2.111 a saw-mill set works, in combina- 'tion, a reciprocating part, and a manuallyment of such periphery of which constitutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained by the pivotal moveart. i

3. In a saw -mill set works, in combination, a reciprocating part, a stop located in the path of such part andcomprising a pivotal member, the periphery of which constitutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained by the pivotal movement of such part, and a hand-wheel mounted with the stop.

4. In a saw-mill set works, in combination, a reciprocating part a sto located in the path of such part and comprising a pivotal member, the periphery of which constitutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained b the pivotal movement of such part, a ban wheel mounted with the stop and having a scale thereon, and fixed pointer cooperating with the scale.

5. In a saw-mill set works, in combination, a reciprocating part, a stop located in the path of such paitand comprising a pivotal member, the periphery of which constitutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained by the pivotal movement of such part, a handwhecl mounted with the stop and having ratchet teeth, and a spring pawl cooperating with the ratchet teeth.

6 I11 a saw-mill set works, in combination, a reciprocating part, a stop located in the path of such part and comprising a pivotal member, the periphery of which constiiutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained b the pivotal movement of such part, a han wheel mounted with the stop and having ratchet teeth, a spring pawl cooperating with the'ratchet teeth, a removable templet carried by the wheel and projecting above its teeth and adapted to have notches cut therein, and a tooth carried by the pawl and riding on the tem let.

7. In a saw-mil set works, in combination, a reciprocating part, a stop located in the path of such part and comprising a pivotal member; the periphery of which constition, a reciprocating part, a stop located in the path of such part and comprising a pivotal member, the periphery of which consti- 1 screw-bolt set in and tutes its abutting face and is substantially in the form of a convolute curve, whereby the finest adjustments may be attained by ally varying radii, whereby the finest adthe pivotal movement of such part, and. a justments may be attained by its pivotal projecting from the movement. 7

DE WITT C. PRESCOTT.v

periphery of such stop constituting its abut- 10 ting face and being curved through graduperiphery of the stop.

9. In a saw-mill set works, in combinai Vitnesses:

tion, a reciprocating part, and a pivotally- LOUIS K. GILLSON,

mounted stop in the path of such part, the CHARLES B. GILLSON. 

